Bagasse-eurnace



UNITED STATES PATENT OFFICE.

LOUIS TREGRE, OF ST. JOHN THE BAPTIST PARISH, LOUISIANA.

BAGASSE-FURNACE.

Specification of Letters Patent No. 24,675, dated July 5, 1859.

.To all 'whom it may concern:

Be it known that I, LoUrs TREGRE, of the parish of St. John the Baptist,in the State of Louisiana, have invented certain new and usefulImprovements in Bagasse-Furnaces, of which the following is a full,clear, and exact description, reference being had to the accompanyingdrawings, forming part of this specification, in which* Figure 1,represents a perspective view of a bag-asse furnace embracing myimprovements, Fig. 2, represents a transverse sectional elevationthrough the furnace and also through the boilers. Fig. 3, represents alongitudinal section through the center of the upper part of thefurnace. Fig. 4, represents a longitudinal section through the rear partof the boiler and chimney.

The great difficulty experienced in the economical use of bagasse as afuel to generate steam in the boilers for the purpose of driving theengine used to actuate the machinery of sugar works, or for otherpurposes, arises mainly from the great amount of moisture contained inthe bagasse, and the necessity of driving off this moisture before thebagasse becomes available as fuel, and can be used without the admixtureof a large proportion of other kinds of fuel to generate steam.

Many varieties and forms of furnaces have been invented for the purposeof drying and burning the bagasse, but most of them require a largeadmiXture of other kinds of fuel, in order to dry the bagassesuiiiciently to make it burn.

The object of my invention is to lessen the amount of other fuel thathas heretofore been necessary to use with the bagasse, for the purposeof generating steam to drive the engine in sugar mills-and my inventionfor effecting this object consists in the application of a double feederto deliver the bagasse to the furnace. so arranged that the bagasse willbe retained in it longer than heretofore, and while in it will beexposed to the direct action of the heat of the furnace, by which, in agreat degree, the moisture is driven off before the bagasse enters thefurnace. And it also consists in forming a chamber between the twofeeders to receive the bagasse as it is delivered by the upper feeder,and retain it until carried down by the lower feeder, and it alsoconsists in constructing theupper feeder of greater capacity than thelower feeder in order to fill the intermediate chamber with the surplusbagasse received by the upper feeder. And it further consists inintroducing an independent current of hot dry air from the boiler flueto the chamber separating the feeders, in order to mingle with the hotair from the furnace after it has passed through the lower feeder, andto pass with it through the bagasse in the chamber, and through theupper feeder.

In the accompanying drawings is represented a bagasse furnace embracingmy improvements, and also the boilers connected with the furnace, and itconsists of a furnace (A) rectangular in form on the eXte rior, andoctangular on the interior, and is arched over and closed at the top,with the exception of an opening (a) of sufficient size to feed thebagasse through.

In the sides of the furnace are openings (m.) which may be 'providedwith doors 1f thought expedient. A side flue (n) from the furnaceconnects with an under flue (L), and an upper flue (K) passing beneaththe boiler and the flue (n) is provided with a sliding door by which thedraft through the flues (K and L) is regulated, or the flame cut offfrom entering the upper flue (K). These flues K and L) are separatedfrom each other the entire length of the boiler by a brick arch, and atthe rear end are two sliding doors (N and O)-the one (N) opens andcloses the passage of the upper flue(K) into the chimney, and the one(O) opens and closes the passage from the lower flue to the chimney, sothat the flame from the furnace may be directed through either or bothfines as occasion requires.

The apparatus for feeding the bagasse to the furnace consists of twohollow cylindrical cases (B and 0,) closed at both endsarranged oneabove the other, and connected by side flanches (b) and between thetwocylinders is an intermediate chamber (G) for the purpose hereinaftermentioned. A longitudinal opening is made-*through the top and bottom ofboth cases in line with each other-and the cases are located directlyover the opening (a) in the top of the furnace. so that the openingthrough the cases will correspond with the opening in the top of thefurnace. Each case is provided with a revolving feeder, consisting of acentral shaft (o) with radial arms or blades-which extend near to theinner periphery in both cases.

The revolving feeder in the upper case (B) is of greater diameter thanthe lower case, and is provided with six radial blades (f) forming sixcompartments in the feeder to receive the bagasse, The lower feeder onlyhas four blades (g) and four Vcompartments, and these blades arepunctured full of holes to allow the heat o-f the furnace to passthrough the lower feeder to the upper.r

The shafts to the feeders extend beyond the end of the case, and haveattached to them sprocket wheels (e) of equal size and are connected byan endless chain passing from one to the other-thus both turn with equalvelocity. Motion is communicated to the feeders from the shaft of theconveyer (E) which carries the bagasse from the rollers to the feeders,and this shafthas on its outer end a sprocket wheel (h.) from which anendless chain passes to the sprocket wheel (I) on the shaft of the upperfeeder. The upper case is provided with a hopper (D) to receive thebagasse from the conveyer.

' AY pipe (F) leads from the flues beneath the boiler to the chamber(G), admitting a current of hot dry air into this chamber to mingle withthe hot air Vfrom the furnace after it has passed through the lowercase.

From the arrangement of the feeders, one above the other, with openingspunctured through the blades of the lowerfeeder, it will be seen thatthe hot air from the furnace passes freely from the lower to `the, upperfeeder-that all the time the bagasse is retained in the feeders it issubjected to the drying influence of the current of hot air. The bagasseis much longer subjected to the vaction of the heat of the furnace whenfed through this double feeder than it is when fed through a singlefeeder as heretofore-- therefore, it comes into the furnace in a muchbetter state for combustion.

The introducing of anindependent current of dry air into the chamberbetween the feeders, greatly facilitates the drying of the bagasse, asthe heat from the furnace, after passing through the lower feeder, ischarged withinoistu're and cooled down-and this independent current ofhot dry air, minglng with the air from the furnace, raises itstemperature and dries it so that it is in a better condition to act uponand dry thebagasse in the upper feeder. Y

The irregularity with which the cane is fed to the vcrushing rollers,causes a corresponding irregularity in the delivery of the bagasse bythe conveyer, to the feeding apparatus; at one time delivering it morerapidly than it is fedto the furnace and overrunning thefeeder, and atanother in insuflicient `quantities to maintain a regular re, andonly'partiallyY filling the feeders. In

constructing the upper feeder of greater capacity than the lower, withan intermediate chamber between, the bagasse is delivered with muchgreater regularity to theV furnace, than with the single feeder, as theinf creased capacity of the upper feeder enables itto receive more thanthe lower feeder can discharge, the surplus of which accumulates in theintermediate chamber, and supplies the lower feeder at the time when thesupply from the rollers. is insufficient to fill the chambers in thelower feeder. This increased capacity of the upper feeder, also forms areservoir to receive and retain the bagasse, as when the lower feederand intermediate chamber are fully supplied, the surplus is retained inthecompartments of the upper feeder, carried around with it anddeposited in the intermediate chamber when there is an insuiiicientsupply from the crushing rollers. By means of this increased size of theupper feeder, not only is the supply of the furnace rendered moreuniform, and the intermediate chamber filled with bagasse, but thebagasse is for a greater length of time subjected to the dryinginfluence of the hot air of the furnace, and is thus in a better statefor combustion.

The capacity of the intermediate chamber may be varied according tocircumstances either increased or diminished and the relative proportionof the feeders varied as circumstances may require.

The upper feeder may be made the same size with the lower feeder, andrun at greater velocity than the lower feeder, which will produce thesame effect in depositing a supply in the intermediate chamber toequalize the feed. V

Having thus described my improvements in bagasse furnaces, what I claimtherein as new and desire to secure by Letters Patent is- Y l. Theemployment of a double feeder arranged substantially as described,withopenings through the blades of thev lower feeder to allow the hot airfrom the furnace to pass from the lower feeder tothe upper feeder forthe purpose set forth. And I also claim, arranging between the twofeeders an intermediate chamber to receive and retain the bagasse as itpasses from the upper to the lower feeder. n

2. And I claim constructing the upper feederof larger size than thelower feeder, with or without an increased number of blades-or inr anequivalent manner for the purpose herein set forth.

3. And I further claim `introducing an independent current of hot dryair into the chamber between the'two feeders substantially as hereindescribed for the purpose set forth.

In testimony whereof I have subscribed my name.

LOS. TREGRE.

Witnesses:

THos. J. BURKE, A. B. PHILIPS.

